"Sanity checking ism't likely to much help except in specific circumstances."
If the day of the week is also given then any ambiguity can be reduced - although not always eliminated - by calculating the possible valid years within a tight range. That then needs to know the ways the names of days of the week might be abbreviated. In some languages they are modified (declined?) by different grammatical contexts.
Some posters use several different formats for different events on a page. If they are Europeans who are going to tour the USA then they might use the US mm/dd/yy format just for those events.
Biting the hand that feeds IT
